Method for measuring substance and testing piece

Abstract

A method of measuring an analyte, comprising a step of measuring a detectable substance by using a reaction system including a formation reaction of the detectable substance based on a chemical reaction of the analyte contained in a sample, wherein a layered inorganic compound is caused to exist in the reaction system including the formation reaction of the detectable substance, whereby high-sensitivity measurement is made possible, the detectable substance can be stabilized to improve accuracy of the measurement, a rate of a chemical reaction is increased to enable quick measurement, and high-sensitivity measurement is made possible even in a reaction system which forms an insoluble substance. Also, it can be provided an analytical testing piece for measuring an analyte, by measuring a detectable substance by using a reaction system including a formation reaction of the detectable substance based on a chemical reaction of the analyte contained in a sample, wherein the testing piece comprises at least one test portion having a detection portion for detecting the detectable substance and contains a layered inorganic compound at least in the test portion, whereby diffusion and elution of a dyestuff or the like is prevented, more sensitive and accurate simple analysis is made possible, and easy handling is possible.

The invention claimed is: 
     
       1. A method for measuring an analyte, comprising:
 a step of forming a detectable substance, which is formed by a chemical reaction of the analyte and a reagent and is formed with a quantitative correlation with the analyte, wherein a reaction system which forms the detectable substance contains a substance which decomposes the detectable substance, and the reaction system which forms the detectable substance contains a layered inorganic compound to suppress decomposition of the detectable substance; and 
 a step of measuring the detectable substance by an electrochemical method, 
 wherein the detectable substance is an electron carrier. 
 
     
     
       2. A method for measuring an analyte, comprising:
 a step of forming a detectable substance, which is formed by a chemical reaction of the analyte and a reagent and is formed with a quantitative correlation with the analyte, wherein a reaction system which forms the detectable substance contains a substance which decomposes the detectable substance, and the reaction system which forms the detectable substance contains a layered inorganic compound to suppress decomposition of the detectable substance; and 
 a step of measuring the detectable substance, 
 wherein the formation reaction of the detectable substance is an oxidation-reduction reaction and the reaction system including the formation reaction of the detectable substance includes a formation reaction of hydrogen peroxide or an oxidation reaction using hydrogen peroxide as an oxidizing agent. 
 
     
     
       3. The method according to  claim 2 , which measures the analyte by colorimetrically determining a quantity of a dyestuff having a quantitative correlation with the analyte and formed by an oxidation-reduction reaction between hydrogen peroxide formed from the analyte through a chemical reaction and an oxidizable color coupler, wherein at least decomposition of the dyestuff by hydrogen peroxide is suppressed by causing the layered inorganic compound to exist in a system of the oxidation-reduction reaction. 
     
     
       4. A method for measuring an analyte, comprising:
 a step of forming a detectable substance, which is formed by a chemical reaction of the analyte and a reagent and is formed with a quantitative correlation with the analyte, wherein a reaction system which forms the detectable substance contains a substance which decomposes the detectable substance, and the reaction system which forms the detectable substance contains a layered inorganic compound to suppress decomposition of the detectable substance; and 
 a step of measuring the detectable substance, 
 wherein the formation reaction of the detectable substance is an oxidation-reduction reaction and the reaction system including the formation reaction of the detectable substance includes the formation reaction of nicotinamide adenine dinucleotide or nicotinamide adenine dinucleotide phosphate or a reaction in which nicotinamide adenine dinucleotide or nicotinamide adenine dinucleotide phosphate acts as a reducing agent. 
 
     
     
       5. A method for measuring an analyte, comprising:
 a step of forming a detectable substance, which is formed by a chemical reaction of the analyte and a reagent and is formed with a quantitative correlation with the analyte, wherein a reaction system which forms the detectable substance contains a substance which decomposes the detectable substance, and the reaction system which forms the detectable substance contains a layered inorganic compound to suppress decomposition of the detectable substance; and 
 a step of measuring the detectable substance, 
 wherein the detectable substance is an azo compound detected by an optical method, and the method measures the analyte by determining a quantity of an azo compound having a quantitative correlation with the analyte and formed by a coupling reaction between a diazonium salt formed from the analyte through a chemical reaction and a coupling reagent, wherein decomposition of the azo compound is suppressed by causing the layered inorganic compound to exist in a system of the coupling reaction.